In typical computer aided imaging techniques, an image of a region or scene is produced and processed in order to analyze it and extract desired data therefrom.
In maritime applications, for example, various imagers are used to survey and monitor maritime scenes (e.g., oceans, seas, rivers, lakes, dams, beaches, borders etc), whereby such surveillance and monitoring may include automatic or semi-automatic (man-in-the-loop, i.e., requiring user intervention/aid) detection of foreign objects in the water. Such detection of foreign objects may include, for example, debris, wreckage, buoys, objects, oil leaks, pollution, swimmers, intruders, mines, boats, rigs etc, and is applicable for example in maritime security, navigation, environmental control and rescue operations.
Various object/event detection techniques have been developed for operating in maritime environments.
For example, CN 101976439 discloses a visual attention model with combination of motion information, which is applied in a visual system of a maritime search and rescue machine. This technique mainly utilizes the characteristics in three aspects of brightness, color and the motion information in image sequence during the implementation, utilizes linear combination strategy for forming a visual saliency map, and obtains the current visual attention focus through competition mechanism to carry out object detection for maritime search and rescue. The motion information is derived from the differentiation result between a current frame of the image sequence and a background image after moving average. The use of the visual attention model can generate a search and rescue object saliency map under the maritime search and rescue dynamic background conditions, and further obtain the visual attention focus. The visual attention model uses a small calculation quantity of the motion information and is convenient to realize. Simultaneously, the method does not need to calculate the directional feature in the traditional visual attention model and can effectively remove the interference caused by a water-sky-line and lead the visual attention model to be more applicable to particular maritime search and rescue environments.
WO 09080903 describes a maritime monitoring system, which comprises a radar connected to calculation means and man-machine interfaces making it possible to view on a screen representing a monitored stretch of water the position of the object or objects detected by the radar. It furthermore comprises a panoramic infrared camera adapted for detecting at least one object on at least a part of the monitored stretch of water and for providing the calculation means with a position of each object relative to said camera, and such that the calculation means are adapted for providing the position of each object detected by the radar and of each object detected by the infrared camera in a common reference frame.